Medical patient support chair

ABSTRACT

A chair for supporting medical patients, especially bariatric patients, includes a skeletal frame; a seat assembly mounted to the frame and including a seat base and a seat back, with the seat base being pivotably mounted to the frame and the seat back being pivotably mounted to the seat base for relative movement of the seat assembly to the frame and relative movement of the seat back to the seat base and the frame. Included is a first movement inducing assembly mounted to the seat base and the frame and extending therebetween for moving the seat assembly relative to the frame and a second movement inducing assembly mounted to the seat base and the seat back and extending therebetween for selectively moving the back relative to the seat back and the frame, substantially independently of the first movement inducing assembly; and a motion control arrangement for operatively controlling the first and second movement inducing assemblies independently of one another for singular or tandem independent movement of the seat back and the seat assembly as necessary for medical patient comfort and care.

BACKGROUND OF THE INVENTION

The present invention relates broadly to furniture for people with special medical needs and more particularly to a bariatric chair with an adjustable seat assembly and is capable of translational movement along the surface.

Bariatric chairs and other bariatric seating provide support for medical patents who may weigh between 500 and 1000 pounds. As may be expected, conventional furniture is not designed for such use. Bariatric chairs are designed to provide support for medical patients with such a need and wheeled versions allow medical attendants to move patients in the chairs.

Bariatric seating should be comfortable for the patient and mobile bariatric seating should be comfortable for an attendant to use to transport a patient. Further, the level of adjustability available for bariatric seating should be extensive so that any individual person can be placed in a position that is most comfortable to him or her while allowing convenient ingress and egress.

Security is also important to bariatric patients and a feeling of stability and support should be offered in such a seating environment. Imparting such a sense of secure stability to bariatric patients enhances the ability of a caregiver to deliver effective care under a reduced stress level. Enhanced stability is also effective in promoting patient self-reliance.

There currently exists a need for bariatric seating that provides enhanced stability and support in a mobile seat with enhanced seat adjustability and control.

SUMMARY OF THE INVENTION

It is currently an object of the present invention to provide a chair for medical patients that will allow the seat bottom to be moved relative to the frame and independently of the seat back.

It is another object of the present invention to provide a chair for medical patients that will allow the back to be moved relative to the seat bottom, and both separately therefrom and in tandem therewith.

It is another object of the present invention to provide a chair for medical patients that will allow the seat bottom to move through various positions while maintaining the angular relationship between the seat bottom and the seat back all the while allowing the seat back to be selectively adjusted with respect to both the frame and the seat bottom.

It is another object of the present invention to provide such a medical chair that is self-propelled for movement along a surface.

To those and other ends, the present invention provides a chair for supporting medical patients, especially bariatric patients, including a skeletal frame and a seat assembly mounted to the frame. The seat assembly includes a seat base and a seat back, the seat base being pivotably mounted to the frame and the seat back being pivotably mounted to the seat base for relative movement of the seat assembly to the frame and relative movement of the seat back to the seat base and the frame. The present invention further includes a first movement inducing assembly mounted to the seat base and the frame and extending therebetween for moving the seat assembly relative to the frame; a second movement inducing assembly mounted to the seat base and the seat back and extending therebetween for selectively moving the seat back relative to the seat back and the frame, substantially independently of the first movement inducing assembly; and a motion control arrangement for operatively controlling the first and second movement inducing assemblies independently of one another for singular or tandem independent movement of the seat back and the seat assembly as necessary for medical patient comfort and care.

Preferably, the present invention further includes a rolling ground support arrangement including rotatable wheels at substantially the outer reaches of the frame, mounted thereto and extending away from the frame for ground contact. It is preferred that the rolling ground support arrangement includes two casters supporting a rear portion of the chair and two fixed wheels supporting a front portion of the chair. It is further preferred that the rolling ground support arrangement includes two casters supporting a rear portion of the chair and two fixed wheels supporting a front portion of the chair, and further comprising a driving arrangement for moving the chair across a friction surface including at least one motor for driving the two fixed wheels, and a drive control arrangement for controlling the driving arrangement and thereby controlling translational movement of the chair.

It is preferred that the driving arrangement include an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer the chair during movement over a friction surface. Preferably, the assembly for driving each fixed wheel includes a drive motor mounted closely adjacent a respective fixed wheel and operatively connected thereto for selectively rotatably driving each fixed wheel individually, each drive motor being connected to the drive control arrangement for selective operation by an operator. It is preferred that the present invention further include a control stick for controlling the drive wheels for movement of the chair responsive to movement of the stick by an operator. The control stick may be movable between a rider control position and an attendant accessible position.

It is preferable that the first and second movement inducing assemblies each include at least one piston/cylinder arrangement operatively associated with said first movement inducing assembly and said second movement inducing assembly. Preferentially, the motion control arrangement is configured to move the chair to a Trendelenburg Position responsive to a switch operatively associated with the movement inducing assemblies.

The present invention can be described in greater detail as a chair for supporting medical patients including a skeletal frame and a seat assembly mounted to the frame and including a seat base and a seat back, the seat base being pivotably mounted to the frame and the seat back being pivotably mounted to the seat base for relative movement of the seat assembly to the frame and relative movement of the seat back to the seat base and the frame. The present invention further includes a first movement inducing assembly mounted to the seat base and the frame and extending therebetween for moving the seat assembly relative to the frame; and a second movement inducing assembly mounted to the seat base and the seat back and extending therebetween for selectively moving the seat back relative to the seat back and the frame, substantially independently of the first movement inducing assembly. Further, the present invention provides a motion control arrangement for operatively controlling the first and second movement inducing assemblies independently of one another for singular or tandem independent movement of the seat back and the seat assembly as necessary for medical patient comfort and care; and a rolling ground support arrangement including rotatable wheels at substantially the outer reaches of the frame, mounted thereto and extending away from the frame for ground contact.

It is preferred that the rolling ground support arrangement includes two casters supporting a rear portion of the chair and two fixed wheels supporting a front portion of the chair. Preferably, the rolling ground support arrangement includes two casters supporting a rear portion of the chair and two fixed wheels supporting a front portion of the chair, and further comprising a driving arrangement for moving the chair across a friction surface including at least one motor for driving the two fixed wheels, and a drive control arrangement for controlling the driving arrangement and thereby controlling translational movement of the chair.

The present invention further preferably includes, within the driving arrangement, an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer the chair during movement over a friction surface. It is further preferred that the assembly for driving each fixed wheel includes a drive motor mounted closely adjacent a respective fixed wheel and operatively connected thereto for selectively rotatably driving each fixed wheel individually, each drive motor being connected to the drive control arrangement for selective operation by an operator. Preferably, the present invention further includes a control stick for controlling the drive wheels for movement of the chair responsive to movement of the stick by an operator. The control stick may be movable between a rider control position and an attendant accessible position.

It is preferred that the first and second movement inducing assemblies each include at least one piston/cylinder arrangement operatively associated with said first movement inducing assembly and said second movement inducing assembly.

Preferably, the motion control arrangement is configured to move the chair to a Trendelenburg Position responsive to a switch operatively associated with the movement inducing assemblies.

The present invention can also be described in greater detail as a chair for supporting medical patients including a skeletal frame and a seat assembly mounted to the frame and including a seat base and a seat back, with the seat base being pivotably mounted to the frame and the seat back being pivotably mounted to the seat base for relative movement of the seat assembly to the frame and relative movement of the seat back to the seat base and the frame. Also included is a first movement inducing assembly mounted to the seat base and the frame and extending therebetween for moving the seat assembly relative to the frame and a second movement inducing assembly mounted to the seat base and the seat back and extending therebetween for selectively moving the seat back relative to the seat back and the frame, substantially independently of the first movement inducing assembly. The present invention further includes a motion control arrangement for operatively controlling the first and second movement inducing assemblies independently of one another for singular or tandem independent movement of the seat back and the seat assembly as necessary for medical patient comfort and care A rolling ground support arrangement is provided that includes two casters supporting a rear portion of the chair and two fixed wheels supporting a front portion of the chair, mounted thereto and extending away from the frame for ground contact. Further provided is a driving arrangement for moving the chair across a friction surface including an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer the chair during movement over a friction surface, and a drive control arrangement for controlling the driving arrangement and thereby controlling movement of the chair.

It is preferred that the assembly for driving each fixed wheel include a drive motor mounted closely adjacent a respective fixed wheel and operatively connected thereto for selectively rotatably driving each fixed wheel individually, each drive motor being connected to the drive control arrangement for selective operation by an operator.

The present invention further preferably includes a control stick for controlling the drive wheels for movement of the chair responsive to movement of the stick by an operator. Also preferably included is an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer the chair during movement over a friction surface wherein the control stick is movable between a rider control position and an attendant accessible position. The first and second movement inducing assemblies may each include at least one piston/cylinder arrangement operatively associated with said first movement inducing assembly and said second movement inducing assembly. The motion control arrangement is preferably configured to move the chair to a Trendelenburg Position responsive to a switch operatively associated with the movement inducing assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a chair for supporting medical patients according to one preferred embodiment of the present invention;

FIG. 2 is a perspective view of the framework associated with the present invention;

FIG. 3 is a perspective underside view of the frame structure of the present invention;

FIG. 4 is a perspective view of partial framework associated with the present invention;

FIG. 5 is a side partial view of the framework association with the present invention used to provide a motion diagram of the seat and back structure thereof;

FIG. 6 is a side partial view of the framework association with the present invention of FIG. 5 with movement inducing assemblies installed;

FIG. 7 is a perspective underside view of the frame structure of the present invention illustrating the drive system components; and

FIG. 8 is a block diagram of the control systems of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to the drawings and, more particularly to FIG. 1, a chair for medical patients, especially bariatric patients, according to the preferred embodiment of the present invention is illustrated generally at 10 and includes a skeletal frame 12, as best seen in FIG. 2 and other subsequent figures. The frame 12 is upholstered and includes chair covers 14 and side panels 24. Fundamental to any chair and provided here are a seat bottom 26 and a seat back 30 as illustrated in FIG. 1. The seat bottom 26 and the seat back 30 are mounted to a seat bottom frame 28 (not shown in FIG. 1) and a seat back frame 32, respectively. The frame structures are best seen in FIG. 2. Since most of the figures herein illustrate a skeletal frame, for clarity reference will be made to movements and connections to the seat bottom frame 28 and the seat back frame 32. Nevertheless, it should be understood that motions applicable to the seat bottom frame 28 and the seat back frame 32 are also imparted to the seat bottom 26 and the seat back 30.

Returning now to FIG. 1, the chair 10 of the present invention also includes arm rests 22 and a foot rest 20 both of which are mounted to the frame 12 with each arm rest 22 being mounted to a side frame 34 and the foot rest 20 being rotatably mounted intermediate two side frame 34 portions.

Since the chair 10 of the present invention is moveable in a translational manner across a surface, a pair of drive wheels 16 is provided at the two front corners of the chair 10 while a pair of casters 18 is mounted at the rear corners of the chair and their 360 degree rotational movement allows for essentially a zero turning radius for the chair as will be seen in greater detail hereinafter.

Turning now to FIG. 2, the chair 10 of the present invention is illustrated without the upholstery and reveals a skeletal frame 12 formed from a series of generally vertical and horizontal cross members extending between two side frame portions 34.

Also revealed in FIG. 2 are the movement inducing assemblies that impart motion to the seat bottom frame 28 and the seat back frame 32. These consist of piston/cylinder arrangements illustrated at 36, 37 and 42 in FIG. 2 and, more clearly, in FIG. 3. Although not shown, it is contemplated that the foot rest 20 may be equipped with a piston/cylinder arrangement so that its movements may be coordinated with the movement of the seat bottom 26 and seat back 30. Further, the foot rest 20 may be mechanically linked to the seat back 30 for coordinated movement therewith. It should be noted that the seat bottom 26 is supported by the seat bottom frame 28 while the seat back 30 is supported by the seat back frame 32.

It will be understood by those skilled in the art that the movement inducing assemblies are not limited to piston/cylinder arrangements and the motion may be accomplished using other means, for example, motors with pinions operating with gear racks.

The piston/cylinder arrangements, also referred to as movement-inducing assemblies, are configured for moving the seat bottom frame 28 relative to the overall frame 12 in partial rotation about a seat/frame pivot point 49 where the seat frame 28 is pivotally joined to the side frame 34. According to the preferred embodiment of the present invention, this motion is accomplished using a pair of piston/cylinder arrangements 36, 37 that form the first movement inducing assembly and are pivotally mounted to a lower boss 38 attached to a lower cross member 39 and an upper boss 40 which is mounted to the seat bottom frame 28. As these pistons and cylinders 36, 37 are caused to extend and contract, the seat bottom frame 28 is caused to rotate about the pivot 49 as will be explained in greater detail hereinafter. The dual nature of the seat bottom piston/cylinder arrangements 36, 37 provides balanced support and provides the necessary strength to move both the seat back frame 32 and the seat bottom frame 28 relative to the overall frame 12 while supporting a bariatric patient.

With continued reference to FIGS. 3 and 4, the second movement inducing assembly is configured as single piston/cylinder arrangement 42 pivotably attached to a lower boss 44 that is fixed to the lowermost cross member 45 on the seat back frame 32 while the other end of the piston/cylinder arrangement 42 is pivotably attached to a boss 46 fixed to the forwardmost cross brace 29 of the seat bottom frame 28. As will be seen, the seat bottom movement inducing assembly 36, 37 is operable independently of the seat back movement inducing assembly 42. The seat back frame 32 is configured for partial rotation about a pivot point 48 where the seat back frame 32 is joined to the seat bottom frame 28.

Referring to FIGS. 5 and 6, motion diagrams illustrate the relationship between the piston/cylinder arrangements 36, 37 and 42 and the respective chair components. In FIG. 5, the piston/cylinder arrangements 37, 42 are illustrated schematically.

Regarding seat motion, the overall frame structure 12 does not move and remains in a ground supported manner on the wheels 16 and casters 18 as seen in FIGS. 1 and 2. The seat bottom frame 28 moves in a rotational manner about pivot point 49 at the forward part of the chair on the arm frame 34. Movement of the seat bottom frame 28 is governed by piston/cylinder arrangement pair 36, 37, each of which is pivotably mounted to the frame 12 and the seat bottom frame 28. FIGS. 5 and 6, being side views, do not illustrate both piston/cylinder assemblies of the pair, but are illustrative with regard to the mounting arrangements, showing piston/cylinder assembly 37 mounted to the frame 12 at boss 38 and the seat bottom frame 28 at boss 40.

Movement of the seat back frame 30 relative to the seat bottom frame 28 is accomplished using the seat back piston/cylinder assembly 42 which is pivotably mounted to the lowermost portion of the seat back frame 30 at boss 44 and pivotably mounted to a forward portion of the seat bottom frame 28 illustrated at 46. Extension and compression of the seat back piston/cylinder 42 results in rotational movement of the seat back 30 about pivot point 48 at the rear most portion of the seat bottom frame 28.

As will be seen in greater detail hereinafter, movement of the seat bottom frame 28 and the seat back frame 30 may take place simultaneously or individually but it should be noted that control of the movement inducing assemblies 36, 37 and 42 are independent operations. Therefore, motion of the seat bottom frame 28 about pivot point 49, as illustrated by arrow A in FIGS. 5 and 6 may be accomplished individually or simultaneously with movement of the seat back frame 30 about pivot point 48 as illustrated by arrow B.

Turning now to FIG. 7, the chair 10 of the present invention is provided with a drive system 50 for translational movement of the chair across a friction surface. The drive system 50 includes the aforesaid wheels 16 disposed at two forward corners of the frame structure 12. The wheels 16 are powered by electric or hydraulic motors with a motor 52, 54 dedicated to each drive wheel. These motors 52, 54 may be engaged simultaneously or individually in order to provide direct general control for the chair 10. As may be expected, movement of one drivel wheel while holding the other stationary results in a “zero-turning radius” as is known in mowers and other vehicles with this drive configuration. The motors 52 are joined by an axle 56 extending therebetween.

In order to control motion of the chair components including translational motion of the chair 10 across the friction surface and relative motion of the seat bottom frame 28 and the seat back frame 32, a control system is provided. The control system is illustrated in block diagram form in FIG. 8, and includes a chair motion controller 62 that is operatively attached to piston/cylinder arrangements 36, 37 and 42 for moving the front and back portion of the seat assembly. The controller may be preprogrammed to achieve certain seating arrangements. For example, controls may be provided to move the chair into a Trendelenburg position automatically. The Trendelenburg position allows bariatric patients to breathe better in emergency situations. The controller 62 may be preprogrammed to achieve other predetermined positions and therefore may be customized for use by a single patient.

A joystick 60 is provided for all controlling all chair motion, both translational movement across a friction surface and movement of the seat back frame 30 and the seat bottom frame 28. As seen in FIG. 8, a selector 64 is provided in operational engagement with the joystick 60. An operator may use the selector to select either the drive system or the chair movement system for selective control by the joystick 60. The selector 64 can also be used to activate preprogrammed chair movements including Trendelenburg Position placement.

The drive controller 36 distributes power to the two electric motors 52, 54 which may also be formed as hydraulic motors. Control of the chairs translational movement is attained through the use of the joystick 60 which provides an intuitive grid for chair movement. In order to move the chair, the selector 64 is used to select chair translational movement and the joystick 60 is directed to whatever direction the occupant or attendant would like to travel. For example, to move the chair in a forward manner, slightly to the left, the joystick is placed off-center forwardly and slightly to the left thereby providing an intuitive steering feel. The joystick 60 may be moved to various points about the chair 10 for access by a patient or a caregiver.

By the above, it can be seen that the present invention provides a sturdy chair for bariatric use which has a significant range of movement to provide for the comfort and health of medical patients undergoing treatment and requiring such a chair.

It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of a broad utility and application. While the present invention is described in all currently foreseeable embodiments, there may be other, unforeseeable embodiments and adaptations of the present invention, as well as variations, modifications and equivalent arrangements, that do not depart from the substance or scope of the present invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. 

1. A chair for supporting medical patients comprising: a skeletal frame; a seat assembly mounted to said frame and including a seat base and a seat back, said seat base being pivotably mounted to said frame and said seat back being pivotably mounted to said seat base for relative movement of said seat assembly to said frame and relative movement of said seat back to said seat base and said frame; a first movement inducing assembly mounted to said seat base and said frame and extending therebetween for moving said seat assembly relative to said frame; a second movement inducing assembly mounted to said seat base and said seat back and extending therebetween for selectively moving said seat back relative to said seat back and said frame, substantially independently of said first movement inducing assembly; and a motion control arrangement for operatively controlling said first and second movement inducing assemblies independently of one another for singular or tandem independent movement of said seat back and said seat assembly as necessary for medical patient comfort and care.
 2. A chair for supporting medical patients according to claim 1 and further comprising a rolling ground support arrangement including rotatable wheels at substantially the outer reaches of the frame, mounted thereto and extending away from the frame for ground contact.
 3. A chair for supporting medical patients according to claim 2 wherein said rolling ground support arrangement includes two casters supporting a rear portion of said chair and two fixed wheels supporting a front portion of said chair.
 4. A chair for supporting medical patients according to claim 2 wherein said rolling ground support arrangement includes two casters supporting a rear portion of said chair and two fixed wheels supporting a front portion of said chair, and further comprising a driving arrangement for moving said chair across a friction surface including at least one motor for driving said two fixed wheels, and a drive control arrangement for controlling said driving arrangement and thereby controlling translational movement of said chair.
 5. A chair for supporting medical patients according to claim 4 wherein said driving arrangement includes an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer said chair during movement over a friction surface.
 6. A chair for supporting medical patients according to claim 5 wherein said assembly for driving each fixed wheel includes a drive motor mounted closely adjacent a respective fixed wheel and operatively connected thereto for selectively rotatably driving each fixed wheel individually, each said drive motor being connected to said drive control arrangement for selective operation by an operator.
 7. A chair for supporting medical patients according to claim 6 and further comprising a control stick for controlling said drive wheels for movement of said chair responsive to movement of said stick by an operator.
 8. A chair for supporting medical patients according to claim 7 wherein said control stick is movable between a rider control position and an attendant accessible position.
 9. A chair for supporting medical patients according to claim 1 wherein said first and second movement inducing assemblies each include at least one piston/cylinder arrangement operatively associated with said first movement inducing assembly and said second movement inducing assembly.
 10. A chair for supporting medical patients according to claim 1 wherein said motion control arrangement is configured to move said chair to a Trendelenburg Position responsive to a switch operatively associated with said movement inducing assemblies.
 11. A chair for supporting medical patients comprising: a skeletal frame; a seat assembly mounted to said frame and including a seat base and a seat back, said seat base being pivotably mounted to said frame and said seat back being pivotably mounted to said seat base for relative movement of said seat assembly to said frame and relative movement of said seat back to said seat base and said frame; a first movement inducing assembly mounted to said seat base and said frame and extending therebetween for moving said seat assembly relative to said frame; a second movement inducing assembly mounted to said seat base and said seat back and extending therebetween for selectively moving said seat back relative to said seat back and said frame, substantially independently of said first movement inducing assembly; a motion control arrangement for operatively controlling said first and second movement inducing assemblies independently of one another for singular or tandem independent movement of said seat back and said seat assembly as necessary for medical patient comfort and care; and a rolling ground support arrangement including rotatable wheels at substantially the outer reaches of the frame, mounted thereto and extending away from the frame for ground contact.
 12. A chair for supporting medical patients according to claim 11 wherein said rolling ground support arrangement includes two casters supporting a rear portion of said chair and two fixed wheels supporting a front portion of said chair.
 13. A chair for supporting medical patients according to claim 11 wherein said rolling ground support arrangement includes two casters supporting a rear portion of said chair and two fixed wheels supporting a front portion of said chair, and further comprising a driving arrangement for moving said chair across a friction surface including at least one motor for driving said two fixed wheels, and a drive control arrangement for controlling said driving arrangement and thereby controlling translational movement of said chair.
 14. A chair for supporting medical patients according to claim 13 wherein said driving arrangement includes an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer said chair during movement over a friction surface.
 15. A chair for supporting medical patients according to claim 14 wherein said assembly for driving each fixed wheel includes a drive motor mounted closely adjacent a respective fixed wheel and operatively connected thereto for selectively rotatably driving each fixed wheel individually, each said drive motor being connected to said drive control arrangement for selective operation by an operator.
 16. A chair for supporting medical patients according to claim 15 and further comprising a control stick for controlling said drive wheels for movement of said chair responsive to movement of said stick by an operator.
 17. A chair for supporting medical patients according to claim 16 wherein said control stick is movable between a rider control position and an attendant accessible position.
 18. A chair for supporting medical patients according to claim 11 wherein said first and second movement inducing assemblies each include at least one piston/cylinder arrangement operatively associated with said first movement inducing assembly and said second movement inducing assembly.
 19. A chair for supporting medical patients according to claim 11 wherein said motion control arrangement is configured to move said chair to a Trendelenburg Position responsive to a switch operatively associated with said movement inducing assemblies.
 20. A chair for supporting medical patients comprising: a skeletal frame; a seat assembly mounted to said frame and including a seat base and a seat back, said seat base being pivotably mounted to said frame and said seat back being pivotably mounted to said seat base for relative movement of said seat assembly to said frame and relative movement of said seat back to said seat base and said frame; a first movement inducing assembly mounted to said seat base and said frame and extending therebetween for moving said seat assembly relative to said frame; a second movement inducing assembly mounted to said seat base and said seat back and extending therebetween for selectively moving said seat back relative to said seat back and said frame, substantially independently of said first movement inducing assembly; a motion control arrangement for operatively controlling said first and second movement inducing assemblies independently of one another for singular or tandem independent movement of said seat back and said seat assembly as necessary for medical patient comfort and care; a rolling ground support arrangement including two casters supporting a rear portion of said chair and two fixed wheels supporting a front portion of said chair, mounted thereto and extending away from the frame for ground contact; a driving arrangement for moving said chair across a friction surface including an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer said chair during movement over a friction surface, and a drive control arrangement for controlling said drive arrangement and thereby controlling translational movement of said chair.
 21. A chair for supporting medical patients according to claim 20 wherein said assembly for driving each fixed wheel includes a drive motor mounted closely adjacent a respective fixed wheel and operatively connected thereto for selectively rotatably driving each fixed wheel individually, each said drive motor being connected to said control arrangement for selective operation by an operator.
 22. A chair for supporting medical patients according to claim 21 and further comprising a control stick for controlling said drive wheels for movement of said chair responsive to movement of said stick by an operator.
 23. A chair for supporting medical patients according to claim 22 and further comprising an assembly for driving each fixed wheel individually in either a clockwise manner or a counterclockwise manner, thereby allowing an operator to steer said chair during movement over a friction surface wherein said control stick is movable between a rider control position and an attendant accessible position.
 24. A chair for supporting medical patients according to claim 20 wherein said first and second movement inducing assemblies each include at least one piston/cylinder arrangement operatively associated with said first movement inducing assembly and said second movement inducing assembly.
 25. A chair for supporting medical patients according to claim 20 wherein said motion control arrangement is configured to move said chair to a Trendelenburg Position responsive to a switch operatively associated with said movement inducing assemblies. 